How do you clean stone slabs on a balcony?

Stone slabs on a balcony should first be swept thoroughly. Sand and grit should not be allowed to abrade the surface during cleaning.

Most dirt can be removed with clean water and a scrubbing brush. Stubborn residues can be worked loose with a pH-neutral cleaner, provided that it is suitable for the particular type of stone. Work the cleaner in with the brush.

Acidic products are not suitable for marble, limestone or travertine, as they can attack the surface. Green deposits in the joints can be removed with clean water and a scrubbing brush.

A pressure washer is suitable only in limited circumstances. Its powerful water jet can wash out jointing material and roughen sensitive stone surfaces.